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Particle Distribution Informed by Chain Rigidity in Diblock Copolymer Melts: The Effect of Entropy

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Chinese Journal of Polymer Science 2024年第3期42卷 388-399,I0009页

作者： Yuguo Chen Shuanhu Qi Ying Jiang School of Chemistry Beihang UniversityBeijing 100191China

We study the effect of chain rigidity on tailoring the nanoparticle locations for neutral and selective particles embedded in the lamellar morphology formed by semiflexible diblock copolymer chains using self-consistent field calculations. The nanoparticles are modeled through a cavity function, and the semiflexible chains are represented by the continuous Kratsky-Porod chain model. In general situation, the nanoparticles prefer to stay at the interface in order to reduce the interface areas and thus the system free energy. However, the particle distribution at the domain center is subtle, and the underlying physics is intrinsically different depending on the polymer flexibility. In the case of flexible chains, the entropy just contributes a constant shift to the free energy when the nanoparticles move around the domain center indicating that the local metastable state if appears at the domain center is wholly attributed to the local minimum in the enthalpy. If the polymers are rigid, the variation of the particle distribution at the domain center has a close relation with the polymer rigidity and nanoparticle size. In the case of strongly rigid polymers with small nanoparticles, a nearly uniform particle distribution at the domain center is observed, while in other cases, a local enhancement of particle distribution there is found. In contrast to the case of flexible chains, further analysis reveals the crucial role of entropy in controlling the shape of particle distributions at the phase domain. Specifically, the local metastable state appears in the domain center is determined by the large entropy there which arises from the weak coupling of bond orientations that allows the polymer chains to be relatively relaxed. When the particle becomes selective, its distribution in the phase domain exhibits a shift almost uniformly rather than changes its profile, and the underlying physics still holds. In all, our study establishes a strong coupling between the chain rigi

关键词： Semiflexible diblock copolymer Nanoparticle distribution Self-consistent field theory Entropic effect

AWells-Riley/based COVID-19 infectiousrisk assessment model combining both short rangeandroom scale effects

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Building Simulation 2024年第1期17卷 93-111页

作者： Yinshuai Feng Yifan Fan Xiaoyu Luo Jian Ge College of Civil Engineering and Architecture Zhejiang UniversityHangzhouChina Center for Balance Architecture Zhejiang UniversityHangzhouChina International research Center for Green Building and Low-Carbon City International CampusZhejiang UniversityHainingChina

There is growing evidence of the high transmission potential of COVID-19 through virus-laden *** aerosols are inhaled in various concentrations,an overall assessment of transmission risks at different indoor scales is ***,a comprehensive risk assessment method that evaluates the direct link between short-range and room-scale zones is stl *** this paper,a risk assessment model combining both short-range and room-scale effects is developed to obtain effective reproduction number in confined indoor environments,called Turbulent Jet Wells Riley(TJWR)*** with the viral load data and aerosol generation data of different human respiratory activities,the Monte Carlo simulation method is applied to calculate the quanta emission rate,which further provides the input parameters of the TJWR *** known outbreaks(Hangzhou banquet hall X,Guangzhou restaurant Y,and Hong Kong restaurant Z,China)are chosen to validate the TJWR *** show that the TJWR model is more efficient than the original Wells-Riley *** average relative error of the TJWR model ranges between 9%and 44%,while for the Wells-Riley model,it ranges between 57%and 78%.The TJWR model also proves that infection risk assessments using the well-mixed assumption can systematically underestimate the transmission risk for those close to the ***,there is a significant positive linear correlation between the total number of exposed individuals at the short-range and the effective reproduction *** newly developed TJWR model has great potential for rapid and real-time overall airborne transmission risk assessment in buildings and cities.

关键词： COVID-19 airborne transmission infection risk Wells-Riley model Monte Carlo simulation

Towards advanced zinc anodes by interfacial modification strategies for efficient aqueous zinc metal batteries

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Journal of Energy Chemistry 2024年第6期93卷 79-110,I0003页

作者： Changchun Fan Weijia Meng Jiaye Ye Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology Ministry of EducationSchool of ChemistryBeihang UniversityBeijing 100191China Shaanxi Key Laboratory of New Transportation Energy and Automotive Energy Saving School of Energy and Electrical EngineeringChang’an UniversityXi’an 710061ShaanxiChina School of Chemistry and Physics Faculty of ScienceQueensland University of TechnologyBrisbaneQLD 4001Australia Centre for Materials Science Queensland University of TechnologyBrisbaneQLD 4001Australia

Developing sustainable and clean energy sources(e.g.,solar,wind,and tide energy)is essential to achieve the goal of carbon *** to the discontinuous and inco nsistent nature of common clean energy sources,high-performance energy storage technologies are a critical part of achieving this *** zinc metal batteries(AZMBs)with inherent safety,low cost,and competitive performance are regarded as one of the promising candidates for grid-scale energy ***,zinc metal anodes(ZMAs)with irreversible problems of dendrite growth,hydrogen evolution reaction,self-corrosio n,and other side reactions have seriously hindered the development and commercialization of *** increasing number of researchers are focusing on the stability of ZMAs,so assessing the effectiveness of existing research strategies is critical to the development of *** review aims to provide a comprehensive overview of the fundamentals and challenges of *** rch strategies for interfacial modification of ZMAs are systematically *** features of artificial interfacial coating and in-situ interfacial coating of ZMAs are compared and discussed in detail,as well as the effect of modified interfacial ZMA on the full-battery ***,perspectives are provided on the problems and challenges of *** review is expected to offer a constructive reference for the further development and commercialization of AZMBs.

关键词： Aqueous zinc metal batteries Zinc metal anode Interfacial modification Artificial interfacial coating In-situ interfacial coating

Ultralow friction PTFE/PEEK heterolayer:A new solid lubrication approach toward simplicity

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Friction 2024年第1期12卷 120-135页

作者： Wei SUN Jiaxin YE Qingrui SONG Yi FENG Xiaojun LIU School of Materials Science and Engineering Hefei University of TechnologyHefei 230009China Institute of Tribology School of Mechanical EngineeringHefei University of TechnologyHefei 230009China

Tribological applications of polytetrafluoroethylene(PTFE)are often limited by technological complexity to overcome its poor wear ***,a PTFE/polyetheretherketone(PEEK)heterolayer(HL)was proposed and evaluated as a new solid lubrication ***-on-disk tribometry found the lowest friction coefficient(μ)of 0.031 and ultralow wear for the PEEK/HL under typical *** friction coefficient of the HL surpasses those of the state-of-the-art polymeric coatings/composites by at least 200%,and approaches that of highly lubricated *** investigations revealed multi-length physical and chemical heterogeneity of the HL that best facilitates a tribofilm with high subsurface stability and surface *** technological simplicity and robustness of the HL’s high lubricity make it a promising new type of solid lubrication toward greater reliability and longevity.

关键词： ultralow friction anti-wear polytetrafluoroethylene(PTFE) heterolayer(HL)

In situ generation of oxyanions-decorated cobalt(nickel)oxyhydroxide catalyst with high corrosion resistance for stable and efficient seawater oxidation

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Journal of Energy Chemistry 2024年第7期94卷 508-516页

作者： Fengting Luo Pei Yu Jueting Xiang Junjie Jiang Shijian Chen Chongqing Key Laboratory of Interface Physics in Energy Conversion College of PhysicsChongqing UniversityChongqing 401331China Center of Modern Physics Institute for Smart City of Chongqing University in LiyangLiyang 213300JiangsuChina

The development of efficient and robust anode materials for stable alkaline seawater electrolysis is severely limited by chlorine evolution reaction and chloride ***,the sulfur-doped cobalt-nickel bimetallic phosphides(CoNiPS)are specifically designed as a pre-catalyst for navigating a surface reconstruction to fabricate the anions(PO^(3-)_(4) and SO^(2-)_(4))-decorated Co(Ni)OOH catalyst(R-CoNiPS)with exceptional durability and high activity for stable alkaline seawater oxidation(ASO).Various experiment techniques together with theoretical simulations both demonstrate that the in situ-generated PO^(3-)_(4) and SO^(2-)_(4) anions on catalyst surface can improve the oxygen evolution reaction(OER)activity,regulating and stabilizing the catalytic active species Co(Ni)OOH,as well as make a critical role in inhibiting the adsorp-tion of chloride ions and extending the service life of ***,this R-CoNiPS electrode exhi-bits superb OER activity toward AsO and stands out among the non-precious ASO electrocatalysts reported recently,requiring low overpotentials of 420 and 440 mV to attain large current densities of 500 and 1000 mA cm^(-2) in an alkaline natural seawater electrolyte,***,the catalyst displays a negligible chloride corrosion at room temperature during ASO operation(>200 h)at 500 mA cm^(-2).This work opens up a new viewpoint for designing high-activity and durable electrocata-lystsforseawaterelectrolysis.

关键词： Seawater electrolysis Anions Oxygen evolution reaction Chloride corrosion

Construction of ternary PEG200-based DESs lubrication systems via tailoring tribo-chemistry

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Friction 2024年第4期12卷 655-669页

作者： Yuting LI Songyu LAN Yazhou LIU Cheng CAO Zicheng TANG Deyin DENG Fuyuan LIU Hao LI Xiaoqiang FAN Minhao ZHU Key Laboratory of Advanced Technologies of Materials(Ministry of Education) School of Materials Science and EngineeringSouthwest Jiaotong UniversityChengdu 610031China Tribology research Institute School of Mechanical EngineeringSouthwest Jiaotong UniversityChengdu 610031China

Designing novel lubricants with easily customized structures,devisable compositions,and simple and economic synthesis over traditional lubricants is critical to fulfilling complex applications,prolonging machine lifetime,and saving *** eutectic solvents(DESs),which show tunable composition,adjustable structure,easy fabrication,and environmental friendliness,are promising candidates for variable and complicated lubricants *** promote the use of DESs as lubricants,a series of PEG200-based DESs with active heteroatoms were fabricated to tailor the tribological performance via ***,PEG200/boric acid(BA)DES shows optimal lubrication performance by forming tribo-chemical reaction film composited of B2O3,iron oxides,and FeOOH,and PEG200/thiourea(TU)DES displays abrasive wear-reducing property by producing FeS tribo-chemical *** the excellent abrasive wear-resistance of PEG200/TU DES and friction reduction of PEG200/BA DES,ternary PEG200/BA/TU DESs,composited of PEG200/TU DES and PEG200/BA DES,are first *** ternary DESs possess superior wettability and thermal stability,which render them potential *** tests of the ternary DESs demonstrate that synergistic lubrication is achieved by forming a transfer film consisting of FexBy,BN,B2O3,and *** FexBy,BN,and B2O3 increase load bearing of the film,and FeS mitigates severe abrasive *** proposed design philosophy of novel DESs as lubricants opens up a unique realm that is unattainable by traditional DESs lubrication mechanisms and provides a platform to design next-generation DESs lubrication systems.

关键词： deep eutectic solvents(DESs) PEG200/boric acid DES PEG200/thiourea DES ternary DESs synergistic lubrication tribo-chemistry

An Assembly of Pyrano[3,2-b]indol-2-ones via NHC-Catalyzed[3+3]Annulation of Indolin-3-ones with Ynals

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Chinese Journal of Chemistry 2024年第13期42卷 1487-1492页

作者： Xia Wang Shulei Zhang Shao-Jie Wang Hao An Xiaolan Xin Haonan Lin Zhifeng Tu Shenci Lu Frontiers Science Center for Flexible Electronics(FSCFE) Shaanxi Institute of Flexible Electronics(SIFE)&Shaanxi Instituteof Biomedical Materials and Engineering(SiBME)Northwestern Polytechnical University(NPU)127 West Youyi RoadXi'anShaanxi 710072China School of Chemistry and Chemical Engineering Northwestern Polytechnical University(NPU)127 West Youyi RoadXi'anShaanxi 710072China

We report herein an unprecedented N-heterocyclic carbene-catalyzed formal[3+3]annulation of ynals with N-Ts indolin-3-ones under the oxidation condition affording the functionalized pyrano[3,2-b]*** alkynyl acylazoliums via the combination of a carbene with ynals in the presence of oxidate proved to be the important intermediates for the success of this *** method features a broad substrate scope and mild conditions,including axially chiral skeletons with suitable substitutions.

关键词： N-Heterocyclic carbene Annulation Organocatalysis Atropisomerism Carbazole Aldehydes Heterocycles Asymmetric catalysis

Solid Desiccant Heat Pump Fresh Air Unit using Composite Silica Gel

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Journal of Thermal Science 2024年第4期33卷 1286-1300页

作者： YANG Tianyu GUO Defang GE Tianshu Institute of Refrigeration and Cryogenics Shanghai Jiao Tong UniversityKey Laboratory of Power Mechanical EngineeringMOE ChinaShanghai200240China Qingdao Haier A/C Electronic Co. LtdQingdao266101China

The introduction of fresh air into the indoor space leads to a significant increase in cooling or heating *** desiccant heat pump fresh air unit which can handle the latent and sensible load of fresh air efficiently have been proposed *** improve the performance of the solid desiccant heat pump fresh air unit in the fresh air handling process,in this paper,the application of composite silica gel in a heat pump fresh air unit was *** comparison between silica gel coating(SGC)and composite silica gel coating(CSGC)shows that the adsorption rate and water uptake capacity of CSGC are more than two times higher than those of *** experimental setup for the solid desiccant heat pump fresh air unit was *** performance of SGC and CSGC was tested in the setup *** show that under summer conditions,compared with the solid desiccant heat pump fresh air unit using silica gel(SGFU),the average moisture removal and COP of the one using composite silica gel(CSGFU)increased by 15%and 30%,*** winter conditions,compared with SGFU,the average humidification and COP of CSGFU increased by 42%and 17%.With optimal operation conditions of 3 min switchover time and 40 r/s compressor frequency,the COP of CSGFU under summer conditions can reach *** also show that the CSGFU and SGFU have higher COP and dehumidification rate under higher outdoor temperature and humidity ratio.

关键词： fresh air system desiccant coated heat exchanger humidification dehumidification experimental comparison

Arbitrary skin metallization by pencil-writing inspired solid-ink rubbing for advanced energy storage and harvesting

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Journal of Energy Chemistry 2024年第1期88卷 592-602,I0013页

作者： Yonghan Zhou Zhongfeng Ji Wenrui Cai Xuewei He Ruiying Bao Xuewei Fu Wei Yang Yu Wang College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065SichuanChina

The development of a durable metallic coating on diverse substrates is both intriguing and challenging,particularly in the research of metal-conductive materials for applications such as batteries,soft electronics,and ***,by learning from the pencil-writing process,a facile solid-ink rubbing technology(SIR-tech)is invented to address the above *** solid-ink is exampled by rational combination of liquid metal and graphite *** harnessing the synergistic effects between rubbing and adhesion,controllable metallic skin is successfully formed onto metals,woods,ceramics,and plastics without limitation in size and ***,outperforming pure liquid-metal coating,the composite metallic skin by SIR-tech is very robust due to the self-lamination of graphite nanoplate exfoliated by liquid-metal *** critical factors controlling the structures-properties of the composite metallic skin have been systematically investigated as *** applications,the SIR-tech is demonstrated to fabricate high-performance composite current collectors for next-generation batteries without traditional metal ***,advanced skin-electrodes are further demonstrated for stable triboelectricity generation even under temperature fluctuation from-196 to 120℃.This facile and highly-flexible SIR-tech may work as a powerful platform for the studies on functional coatings by liquid metals and beyond.

关键词： Microadhesion guided technology Skin metallization by solid-ink rubbing Liquid metal composites Composite current collector Batteries and triboelectric nanogenerators